Apparatus for measuring hemodynamic parameters

ABSTRACT

The present invention is directed toward an ultrasonography apparatus for measuring and/or monitoring hemodynamic activity, such as blood flow. The present invention comprises a doppler ultrasound unit, one or more transducers and a display.

CROSS REFERENCE TO RELATED APPLICATIONS

This is a continuation application of application Ser. No. 10/827,454,filed on Apr. 19, 2004, which is a continuation of application Ser. No.10/134,356, filed on Apr. 27, 2002, which is a continuation ofapplication Ser. No. 09/732,274, filed on Dec. 7, 2000, now U.S. Pat.No. 6,428,478, which is a divisional of application Ser. No. 09/315,867,filed on May 29, 1999, now U.S. Pat. No. 6,221,021, which is acontinuation in part application of application Ser. No. 08/926,209,filed on Sep. 9, 1997, now U.S. Pat. No. 5,947,901.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention is directed toward an ultrasonography apparatusfor measuring and/or monitoring hemodynamic activity, such as bloodflow.

2. Description of the Prior Art

Erectile dysfunctionality may result from neurogenic, vasculogenic,hormonal, and/or psychogenic causes. The term “erectiledysfunctionality”, as used herein, refers to the inability or impairedability of a male patient to experience a penile erection. Theurological arts have developed a number of therapies for treatingerectile dysfunctionality. These therapies include psychological,pharmacological, and electrical charges.

A method and device for electrically stimulating a penile erection isdisclosed in U.S. Pat. No. 4,585,005 to Lue et al. The method disclosedin Lue includes the implantation of an electrode on the cavernous nerve.The electrodes of Lue are connected to a receiver that is subcutaneouslyimplanted in the patient. The method and device disclosed in Luerequires surgery. Additionally, if the device disclosed in Luemalfunctions, surgery is required to remove it. Surgery is expensive andtime consuming. Additionally, many patients may have emotional orpsychological aversions to having electrodes implanted in their penis.

An apparatus for electrically stimulating penile tissue to cause apenile erection is disclosed in U.S. Pat. No. 5,571,118 to Boutos.Boutos discloses the use of a ring having a conductive surface that isplaced on the penis and/or the scrotum. There exists a risk that such adevice may short circuit, if used in an electrically conductiveenvironment, such as a hot tub. This is a major drawback of externalelectrical therapies, as contrasted with external ultrasound therapies.The use of ultrasound transducers on submerged patients has been appliedin other nonanalogous arts, such as extracorporeal shock wavelithotripsy.

An apparatus for electrically simulating a penile erection is disclosedin U.S. Pat. Nos. 4,542,753 and 4,663,102 to Brennan et al. Brennandiscloses a body; member for insertion into the rectum of a patient. Thebody member comprises surface mounted electrodes. Brennan teachesinsertion of the body member sufficiently deep into the patient for atleast one electrode to contact the prostate gland. The device disclosedby Brennan is highly invasive. Patients may experience physicaldiscomfort from the rectal insertion of the device disclosed in Brennan.

Pharmacological therapies for erectile dysfunctionality include theinjection of drugs into the penis. Such methods are disclosed in U.S.Pat. No. 5,236,904 to Gerstengerg et al. and U.S. Pat. No. 4,127,118 toLatorre. Many male patients find the thought of jabbing a hypodermicneedle into their penis to be discomforting. Penile injections may alsoresult in the buildup of scar tissue, bleeding, and persistent prolongederection (priapism). The unacceptability of therapies requiring theintracavernosal injection of drugs into the penis is well documented inthe urological arts (See U.S. Pat. No. 5,482,039 to Place et al. andU.S. Pat. No. 5,731,339 to Lowrey; and Padma-Nathan, Treatment of MenWith Erectile Dysfunction With Transurethral Alprostadil, The NewEngland Journal of Medicine, 336:1-7, Jan. 2, 1997).

Other pharmacological therapies for erectile dysfunctionality includedelivering a drug directly into the urethra of a patient. Methods anddevices for transurethral delivery of drugs into the penis are disclosedin U.S. Pat. Nos. 5,242,391 and 5,482,039 to Place et al. Thesetransurethral drug delivery methods involve inserting a shaft into theurethra The insertion of a shaft up the urethra may cause discomfort inmany patients or be objectionable for many of the same reasons thatpenile hypodermic needle injections are objectionable.

Pharmacological agents for the treatment of erectile dysfunctionality,including vasodilators such as phosphodiesterase (PDE) inhibitors, oralpha adrenergic blockers, may also be delivered orally, transmucosally,transdermally, intranasally and/or rectally. Oral medications areavailable, pursuant to U.S. Food & Drug Administration (FDA)regulations, under the trademarks VIAGRA (a PDE inhibitor) from Pfizer,Inc. of New York, N.Y., and VASOMAX (an alpha adrenergic blocker) fromZonagen, Inc. of The Woodlands, Tex., or its licensees. Such oralmedications are described in U.S. Pat. No. 5,731,339 to Lowrey and U.S.Pat. No. 5,565,466 to Gioco, et al. Orally, transmucosally,transdermally, intranasally, and/or rectally ingested pharmacologicalagents for the treatment of erectile dysfunctionality must be dissolvedinto the blood stream and transported through the body to the penis.Methods of transporting such pharmacological agents to a desired site ofeffect, are disclosed in U.S. Pat. No. 5,565,466 and are incorporatedherein, in their entirety. The time required for such pharmacologicalagents to be dissolved into the blood stream and transported to a sitewhere they will relax the smooth muscle tissue in the corpora cavernosa,resulting in increased penile hemodynamic activity sufficient to causean erection (referred to herein as the “circulatory medication responsetime”), can be as long as one hour. This time period can beunsatisfactory to many men and their consorts, who desire spontaneity intheir sexual relations.

The present invention provides an ultrasonic therapy for hemodynamicstimulation of the penis that does not require (1) the injection ofdrugs into the penis, (2) surgical implantation of electrodes into thepenis, or (3) the insertion of electrodes into the rectum. The method ofthe present invention may be used in an electrically conductive medium,such as a pool or hot tub, without the short circuiting risk present inprior art methods of electrotherapy for penile dysfunctionality. Thepresent invention may be used to reduce the circulatory medicationresponse time by accelerating the circulation of blood comprising avasoactive or vasodilating agent, thereby reducing its transport time.

SUMMARY OF THE INVENTION

Blood is the hydraulic driving fluid that provides the mass increase andforce which result in a penile erection. Under normal conditions, apenile erection occurs when the mass flow rate of blood into the penisexceeds the mass flow rate of blood out of the penis for a certain timeinterval. Vasculogenic erectile dysfunctionality may result from arestriction or blockage of blood flow into the penis or from excessblood flow out of the penis. The present invention is aimed at treatingvasculogenic erectile dysfunctionality that results from inadequateblood flow into the penis.

The present invention provides a method for stimulating hemodynamicactivity within a penis. The first method step of the present inventionis coupling an ultrasound source to a penis. Genital lesions, such aswarts or herpes simplex Type-2 lesions, can absorb and/or attenuateultrasound thereby reducing the therapeutic effectiveness of the presentinvention. Accordingly, in a preferred embodiment, the ultrasound sourceis coupled to a lesion free region of the outer surface of a penis.

The second method step of the present invention is transmittingultrasound energy into the corpora cavernosum of the penis at asufficient frequency and intensity to increase hemodynamic flow withinthe penis. The frequency used is a function of the depth of desiredpenetration into the corpora cavernosum.

Initially, a frequency in the range of 2.5-3.5 MHz is desirable. Ashemodynamic activity in the penis increases and the penis expandscircumferentially, it is desirable to reduce the frequency of ultrasoundenergy from the initial frequency to a reduced frequency in the range of1.8-2.5 MHz. The precise values of initial and reduced frequencies willbe a function of the diameter of the penis being treated.

A portion of the ultrasound energy transmitted into the body isconverted to thermal energy. The increased blood flow resulting from theuse of the present invention provides a thermal transport medium fortransporting and dispersing thermal energy introduced from thetransmission of ultrasound energy. This thermal transport helps tominimize localized temperature increases within the penis. In apreferred embodiment, the ultrasound energy is emitted from one or moreultrasound transducers housed within a portable housing. Localizedtemperature increases can be further minimize by moving the portablehousing relative to the penis being treated so as to disperse thetransfer of thermal energy in the corpora cavernosum.

The present invention also provides a method for monitoring the effectof the stimulation therapy of the present invention. The presentinvention also includes ultrasonographically measuring one or morehemodynamic parameters within the penis. These hemodynamic parametersmay include blood flow velocity, blood pressure, and/or bloodtemperature. The measured hemodynamic parameters can be graphicallydisplayed to provide a real time indication of hemodynamic and/orthermal-hydraulic parameters within the penis. The measured hemodynamicparameters may be transmitted to a remote terminal for analysis by aremotely located health care professional. Alternatively, the measuredhemodynamic parameters may be analyzed by an expert system locatedeither remotely or with the patient.

The present invention is also directed toward an apparatus forstimulating hemodynamic activity within a penis. The apparatus of thepresent invention comprises an ultrasound generator, and a portablehousing coupled to the ultrasound generator. The housing comprises atleast one ultrasound trigger and a first transducer mounting assembly.

The apparatus of the present invention may also be used toultrasonographically measure and/or display one or more hemodynamicparameters.

DESCRIPTION OF THE DRAWINGS

FIG. 1A is a block diagram of a first method embodiment of the presentinvention.

FIG. 1B is a block diagram of a second method embodiment of the presentinvention.

FIG. 2 is a front view of a first apparatus embodiment of the presentinvention.

FIG. 3 is a block diagram of a second apparatus embodiment of thepresent invention.

FIG. 4 is a side cross sectional view of the rotatable adjusting wheelof the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The apparatus of the present invention comprises an ultrasound generator8 and a portable housing 10 coupled to the ultrasound generator, asshown in FIG. 2. The portable housing comprises a first transducermounting assembly 18. In a preferred embodiment, the first transducermounting assembly is curved. An ultrasound trigger 11 is mounted in thehousing and electrically coupled to the generator.

In a preferred embodiment, the ultrasound generator is capable ofselectively generating pulsed or continuous wave ultrasound energy. Thisselective generation may be accomplished by a control knob or switch 7,as shown in FIG. 2. In a preferred embodiment, the ultrasound generatorfurther comprises frequency controls 6 and intensity controls 7, asshown in FIG. 2. In a preferred embodiment, the ultrasound generator iscapable of generating ultrasound energy within a frequency range of1.8-3.5 MHz and within an intensity range of 1.0-2.0 watts/squarecentimeter.

In a preferred embodiment, a position adjuster is coupled to the firsttransducer mounting assembly. In the preferred embodiment shown in FIGS.2 and 4, the adjuster comprises a threaded rod 14 and a rotatableadjusting wheel 16, comprising a centrally located female threadedchannel 17. The channel threadably engages the rod such that when thewheel is rotated, the rod is axially displaced.

It is known in the ultrasound arts that a satisfactory ultrasoundcoupling is necessary for effective delivery of ultrasound energy to apatient for therapeutic or diagnostic purposes. The position adjusterprovides a mechanism for maintaining a satisfactory ultrasound couplingas the penis expands circumferentially as a result of increasedhemodynamic activity. As shown in FIG. 2, the position adjuster can beused to control the separation distance between the first and secondmounting assemblies, 18 and 24. The position adjuster also makes thepresent invention suitable for use with different patients having variedphysical sizes.

The apparatus and method of the present invention may be practiced bythe patient, after proper training, without assistance from anotherperson. In the preferred embodiment shown in FIG. 2, the portablehousing has a pistol type grip, thereby allowing the user to operate thetrigger or triggers with one hand, while manipulating the positionadjuster with the other hand, as needed to maintain a suitableultrasound coupling during penile expansion. The placement of thetriggers and axial position adjuster on opposite sides of the housingfacilitates the user's ability to easily use both hands tosimultaneously manipulate the trigger and the position adjuster.

In a preferred embodiment, the invention further comprises an secondtransducer mounting assembly 24 mounted across from the first transducermounting assembly. In a preferred embodiment, the second transducedmounting assembly is mounted in alignment with the first transducermounting assembly. In another preferred embodiment, the secondtransducer mounting assembly is curved. The second transducer mountingassembly is coupled to the position adjuster. In a preferred embodiment,the radii of curvature of the first and second transducer mountingassemblies are sized such that the first and second transducers can becoupled to the outer surface of a penis.

A first ultrasound emitter 19 is mounted in the first transducermounting assembly. The first transducer is connected to the ultrasoundtrigger and to the ultrasound generator. Electrical and/or electroniccircuitry suitable for connecting ultrasound transmitters to anultrasound generator are described in the following U.S. Patents: U.S.Pat. No. 3,735,756 to Richards; U.S. Pat. No. 5,578,060 to Pohl et al.;and U.S. Pat. No. 4,484,569 to Driller et al. The full disclosures ofthese U.S. Patents is incorporated herein by reference.

A second ultrasound transducer 22 is mounted in the second transducermounting assembly, as shown in FIG. 2. The second ultrasound emitter isconnected to the ultrasound trigger and to the ultrasound generator. Ina preferred embodiment, the first and second ultrasound emitterscomprise a multiplicity of transducers, as shown in FIG. 2.

In the preferred embodiment shown in FIGS. 2-3, the invention furthercomprises an ultrasonography generator 30 connected to at least onetransducer in each transducer mounting assembly and an ultrasonographytrigger 12 mounted in the portable housing and connected to theultrasonography generator. In a preferred embodiment the ultrasonographygenerator and the ultrasound generator are each connected to at leasttwo ultrasound transducers in each of the transducer mountingassemblies. In a preferred embodiment the ultrasonography generator is adoppler ultrasound unit.

The ultrasonography generator is suitable for monitoring penilehemodynamic parameters, such as blood flow. Ultrasonographic apparatussuitable for use with the present invention are disclosed in thefollowing U.S. Patents: U.S. Pat. No. 4,612,937 to Miller; and U.S. Pat.No. 4,334,543 to Fehr. The full disclosures of these two patents areincorporated herein by reference. In a preferred embodiment, theultrasonography generator may comprise a display 32 for displayingmeasured hemodynamic parameters and/or an expert system 33 capable ofanalyzing measured hemodynamic parameters. The expert system is capableof comparing one or measured hemodynamic parameters to preestablishedparameter limits, such as maximum blood pressure or maximum bloodtemperature. The expert system is further capable of generating aninstruction to the user to stop ultrasound therapy if predeterminedparameter limits are exceeded. These instructions may be generated viathe display on the ultrasonography generator or by other visual oraudible means of communication.

In another embodiment, the expert system is capable of generating anopen circuit signal to the ultrasound generator in the event thatpreestablished limits are exceeded for selected hemodynamic parameters.In this embodiment, the expert system functions as a control circuit forthe ultrasound generator. In a preferred embodiment, measuredhemodynamic parameter data may be transmitted to a remote location by avariety of data transmission means, including telephone lines andwireless communication.

The present invention also provides a method for stimulating hemodynamicactivity within a penis, as shown in FIGS. 1A-1B. The method comprisescoupling an ultrasound source to the outer surface of a penis, as shownin block 40 of FIG. 1A. In a preferred embodiment the source ofultrasound energy is coupled to a lesion free region on the outersurface of the penis. In a preferred embodiment the source of ultrasoundenergy comprises at least two ultrasound transducers, placed on oppositesides of the penis, as shown in FIG. 2. In another preferred embodimentthe source of ultrasound energy comprises a portable housing comprisingthe transducers.

The method further comprises transmitting ultrasound energy into thecorpora cavernosum of the penis at a sufficient frequency and intensityto increase hemodynamic flow within the penis, as shown in block 42 ofFIG. 1A. It is known in the ultrasound arts that 1 MHz ultrasound has ahalf value layer of 3.0 cm in muscle, while 3 MHz ultrasound has a halfvalue layer of 1.0 cm in muscle. The term “half value layer”, as usedherein refers to the distance that ultrasound energy travels in a mediumbefore half of the energy is absorbed. The half value layers of variousultrasound frequencies in muscle are disclosed in U.S. Pat. No.5,413,550 to Castel. It is desirable that the frequency used be suchthat its half value layer will be less than the diameter of the penisbeing treated. In a preferred embodiment of the present invention, thefrequency is adjusted such that it has a half value layer of less thanthe diameter of the penis being treated, as the penis expandscircumferentially, as shown in blocks 46 and 48 of FIG. 1A. In apreferred embodiment, the ultrasound energy should be applied at anintensity or power density of 1.0-2.0 watts/square cm.

The transmission of ultrasound energy may be either pulsed orcontinuous. In a preferred embodiment the invention further comprisesrestricting the venous outflow of blood from the penis, as shown inblock 44 of FIG. 1A.

In another preferred embodiment the invention further comprisesultrasonographically measuring one or more hemodynamic parameters withinthe penis, as shown in blocks 50 and 66 of FIGS. 1A and 1B,respectively. In a preferred embodiment, the ultrasonographic measuringmay be performed with a doppler ultrasound unit.

In a preferred embodiment the ultrasonographic measuring comprises ameasurement of blood flow velocity or blood pressure. In anotherpreferred embodiment the transmitting and measuring steps are performedin alternating series. In a preferred embodiment, the invention furthercomprises displaying said measured hemodynamic parameters, as shown inblock 52 of FIG. 1A.

The present invention is also directed to method for accelerating thedelivery of a vasodilating agent to produce a penile erection as shownin FIG. 1B. This embodiment of the invention comprises ingesting avasodilating agent into the body at a point of ingestion external to thepenis, as shown in block 60 of FIG. 1B. In a preferred embodiment, thevasodilating agent is a PDE inhibitor or an alpha adrenergic blocker. Inanother preferred embodiment, the vasodilating agent is phentolaminemesylate, phentolamine hydrochloride, phenoxybenzamine yohimbine,organic nitrates, thymoxamine, imipramine, verapamil, isoxsuprine,naftidrofuryl, tolazoline, or papaverine. In a preferred embodiment theingesting is transmucosal, transdermal, intranasal, or rectal ingesting.In another preferred embodiment, the ingesting is oral.

The invention further comprises coupling an ultrasound source to alesion free region of the outer surface of a penis, as shown in block 62of FIG. 1B. The invention further comprises transmitting ultrasoundenergy into the corpora cavernosum of the penis at a sufficientfrequency and intensity to increase hemodynamic flow within the penis,as shown in block 64 of FIG. 1B.

The embodiments of the invention disclosed herein are illustrative andexplanatory. Various changes in size, shape, material, as well as in thedetails of construction illustrated herein may be made without departingfrom the scope of the invention.

1. An apparatus for measuring at least one hemodynamic parameter,comprising: a. a doppler ultrasound unit comprising a display mounted inthe unit, said unit being capable of displaying at least one measuredhemodynamic parameter; b. a portable housing sized to be grasped in auser's hand; c. a switching mechanism mounted in said housing andoperatively connected to the unit, the switching mechanism being capableof actuating the unit; d. a transducer mounting assembly connected tothe housing by at least one wire such that the distance between theassembly and the housing can be adjusted by a user using only one hand;and e. at least three ultrasound transducers mounted in the assembly andoperatively connected to the switching mechanism.
 2. The apparatus ofclaim 1, wherein the transducer mounting assembly comprises a curvedsurface and the transducers are mounted on the curved surface along acurved path.
 3. The apparatus of claim 1, wherein the measuredhemodynamic parameter is blood flow.
 4. The apparatus of claim 1,wherein the unit comprises a system capable of analyzing at least onemeasured hemodynamic parameter, said system being physically locatedwithin the unit.
 5. The apparatus of claim 4, wherein the unit is adirectional color doppler ultrasound unit capable of indicating thedirection of measured blood flow by a color display of blood flow. 6.The apparatus of claim 4, wherein the system is further capable ofgenerating an instruction to the user.
 7. The apparatus of claim 1,wherein the unit is capable of transmitting ultrasound energy in acontinuous mode and in a pulsed mode.
 8. The apparatus of claim 7,wherein the unit further comprises a control device for selectingbetween a continuous and pulsed mode of operation.
 9. The apparatus ofclaim 8, wherein the control device is a rotatable knob positioned belowthe display.
 10. The apparatus of claim 1, wherein the unit comprises aphase shift circuit.
 11. The apparatus of claim 10, wherein the unit isconfigured to process an in phase signal having a first phase angle anda second signal having a phase shifted 90 degrees from the first phase.12. The apparatus of claim 1, wherein the switching mechanism is a pushbutton.
 13. The apparatus of claim 1, wherein the transducer mountingassembly is further connected to the housing by: a. a threaded rod; andb. a rotatable adjusting wheel comprising a centrally located femalethreaded channel which threadably engages the rod, such that when thewheel is rotated, the rod is axially displaced.
 14. The apparatus ofclaim 1, wherein the doppler ultrasound unit is physically separate fromthe housing.
 15. An apparatus for measuring at least one hemodynamicparameter, comprising: a. a doppler ultrasound unit comprising arectangular display mounted in the unit, said unit being capable ofdisplaying at least one measured hemodynamic parameter; b. a portablehousing sized to be grasped in a user's hand; c. a switching mechanismmounted in said housing and operatively connected to the unit, theswitching mechanism being capable of actuating the unit; d. a transducermounting assembly connected to the housing by at least one wire suchthat the distance between the assembly and the housing can be adjustedby a user using only one hand; and e. at least three ultrasoundtransducers mounted in the assembly and operatively connected to theswitching mechanism.
 16. The apparatus of claim 15, wherein thetransducer mounting assembly comprises a curved surface and thetransducers are mounted on the curved surface along a curved path. 17.The apparatus of claim 1, wherein the unit comprises a phase shiftcircuit.
 18. The apparatus of claim 1, wherein the unit is capable oftransmitting ultrasound energy in a continuous mode and in a pulsedmode.
 19. An apparatus for measuring blood flow: a. a doppler ultrasoundunit comprising a display mounted in the unit, said unit being capableof displaying blood flow measured by the doppler ultrasound unit; b. aportable housing sized to be grasped in a user's hand; c. a switchingmechanism mounted in said housing and operatively connected to the unit,the switching mechanism being capable of actuating the unit; d. a curvedtransducer mounting assembly connected to the housing by at least onewire such that the distance between the assembly and the housing can beadjusted by a user using only one hand; and e. at least three ultrasoundtransducers mounted in the assembly and operatively connected to theswitching mechanism.
 20. The apparatus of claim 1, wherein the unit iscapable of selectively transmitting ultrasound energy in a continuousmode and in a pulsed mode.